Integrated pilot protective and restraint system

ABSTRACT

An integrated pilot protection and restraining system having a circular bearing structure configured to surround the neck of the wearer, and a non-conformal helmet which is detachably coupled to and rotatably supported by the bearing structure. An automatic helmet rotation system is provided for controlling rotation of the helmet in response to movements of the wearer&#39;s head in order to maintain the helmet in a predetermined position with respect to the wearer&#39;s head. The system further includes a restraining anchor disposed on a rear portion of the bearing structure at its non-rotating base proximate to the base of the wearer&#39;s neck. The restraining anchor is coupled to a retractable restraining device.

This is a divisional of copending application Ser. No. 07/874,973 filedon Apr. 27, 1992, now U.S. Pat. No. 5,208,514.

FIELD OF THE INVENTION

The invention relates to personal pilot protective systems, includinghelmets and body restraints, of the type worn by crew members of highperformance fighter aircraft.

BACKGROUND OF THE INVENTION

With the recent advent of high performance fighter aircraft capable ofsustained high acceleration (9+G_(Z)) and high altitude (+50,000 feet)flight, air crew protection performance has become a major limitation inaircraft operation. This is due to both current standard equipmentdesign limitations and the lack of integration by design.

The provision of head protection and bodily restraint in conventionalhelmet configurations presents a major limitation in protectionperformance. With respect to state of the art helmet configurations,human factors such as comfort, stress and fatigue are performancelimiting, principally because the entire head (eyes, ears, neck) is notprotected. Additionally, in a high sustained (+G_(Z)) accelerationenvironment, the weight of the head born helmet configuration compoundsrather than ameliorates air crew G-loading induced difficulties. Forexample, conventional helmet configurations which includeoxygen-communication masks may weigh up to 7 pounds. While the weight ofsuch headborne components are of limited concern during low accelerationflight of an aircraft, they may have drastic effects on the pilot duringhigh acceleration of the aircraft. The high G-forces imposed on thepilot effectively multiply the weight of the helmet and, therefore,increase the head and neck stress of the pilot during attempted headmovements. It is therefore highly desirable to provide a helmet which isnot burdensome to the pilot's head and neck during G-force acceleration,and which is easily rotatable to maximize visibility.

Conventional pilot restraint devices, such as lap or upper body straps,restrain the pilot's torso both in flight and during an ejectionsequence. However, the pilot's neck and head are free to move forward,in a lateral direction, or rotate in order to achieve desired viewingpositions. Also, conventional straps have been found to be inadequate incorrectly positioning the pilot in the ejection seat during ejection.The correct position involves the pilot's head, neck, and spine beingaligned along the axis of propulsion of the ejection seat from theaircraft. Injuries may occur to the pilot by contact with parts of theaircraft or simply as a result of the high acceleration of the ejectionseat as it is propelled from the aircraft. It is therefore desirable toprovide a restraining system which both allows freedom of movement ofthe upper body and head within the cockpit during normal flight andenhances alignment and restraint of the upper body and head of the pilotboth in flight and during the ejection sequence.

SUMMARY OF THE INVENTION

The above objects are achieved in the integrated pilot protection andrestraint system according to the present invention. The system includesa circular bearing structure configured to surround the wearer's neck,and a helmet which is detachably helmet defines a chamber in which thewearer's head may freely rotate. A means is provided for rotating thehelmet in opposite directions on the bearing structure. Control meansare further provided for controlling the rotating means to rotate thehelmet in response to movements of the wearer's head in order tomaintain the helmet in a predetermined position with respect to thewearer's head. According to a further aspect of the invention, arestraining anchor is disposed on a rear portion of the bearingstructure at its non-rotating base proximate to the base of the wearer'sneck. The restraining anchor is coupled to a retractable restrainingdevice.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a helmet and a vest assembly inaccordance with the present invention;

FIG. 2 is a perspective view of a cap-type communications carrier inaccordance with the invention;

FIG. 3 is a side view of the helmet, communications carrier, and vestassembly as worn by a pilot;

FIG. 4 is a schematic block diagram of the helmet and an automatichelmet rotation system in accordance with the present invention;

FIGS. 5 and 6 are respective side and top plan views of the helmetrotation and pilot restraining systems in accordance with the presentinvention; an

FIG. 7 is a perspective view of a restraint anchor coupled to the rearbase of a disconnect bearing of the present invention.

DETAILED DESCRIPTION OF THE ILLUSTRATED EMBODIMENTS

With reference to FIG. 1, a non-conformal full pressure helmet 10 isshown associated with a pressure vest assembly 12. It will beappreciated that the vest assembly may also be configured with apressure coverall or torso garment. The helmet 10 is non-conformal inthat the weight of the helmet is not headborne by the pilot utilizingit, thus G-force acceleration induced head-neck stress and fatigue dueto helmet loading is eliminated. Since the helmet is non-conforming tothe wearer's head, it need not personalized and assigned to a specificpilot. Rather, the helmet may be utilized in a universal pool ofhelmets, thus reducing the inventory of helmets required.

The helmet 10 utilizes a standard full pressure oxygen breathing systemvia oxygen supply hose 14 which, when integrated with the pressure vest12, provides fully balanced breathing at any pressure. The helmet isalso configured to include a large, moveable electrically heated visor16 which provides a wide field of view. The visor may be constructedfrom two-ply laminated acrylic/polycarbonate. The large viewing areaprovides outstanding an effortless visibility in both vertical andhorizontal planes. A wire heating grid may be laminated between the twoplies of the visor at critical visual areas for defogging under lowambient temperature conditions.

The visor is fitted to the helmet by shrouded pivot mechanisms 17 at thesides. A lever 17l, which connects the pivot mechanisms, serves as thevisor opening and closing mechanism. The pivot mechanisms are configuredwith a shroud in order to minimize potential interference with parachuterisers. A lip seal 16s is integrated with the helmet shell around thevisor opening for providing a visor seal requiring minimal sealingforce. A bi-lock mechanism 16l at the lower center front of the helmetsecures the lever 17l in the closed position. An independently operatedsunshade 18 is affixed externally to the visor and integrated with thepivot mechanisms for providing glare protection. Optional laser ornuclear flash protection visors may be substituted for the sunshade.

In addition, a low profile feeding/drinking port 16p may be installed inthe lower portion of the visor where it does not interfere with normalvisibility. A differential pressure operated anti-suffocation valve 16vis disposed in the helmet shell to enable breathing when the normalbreathing gas supply is depleted or inadvertently disconnected. Anelectrical cable assembly 30 provides communications wiring to thehelmet and electrical power wiring to the electrically heated visor.

A rotational bushing assembly 20 is provided at the bottom periphery ofthe helmet. The rotational bushing assembly is configured to bereleasably coupled to a disconnect bearing assembly 24 associated withthe vest assembly 12. As the helmet is non-conformal to the user's head,under normal circumstances there is no direct mechanical connection orcontact between the head and helmet, thus helmet rotation may beaccomplished either manually (by hand or nudging by the head) or via anautomatic helmet rotation system described hereinafter. Rotation of thehelmet accommodates visibility in all directions. The rotational bushingassembly 20 and the disconnect bearing assembly 24 are configured toprevent inadvertent rotation under G-force loading conditions, yetprovide ease of manual (override) rotation.

The vest assembly 12, which in effect acts as the platform for thehelmet 10 and the disconnect bearing assembly 24, is secured to thepilot's torso with restraint straps 22. The vest assembly fits snuglyaround the neck and shoulders of the user and includes a neck seal 26for maintaining a positive breathing pressure within the helmet 10.Additional features of the vest assembly include an exhalation valve 28integrated with the neck seal 26, a breathing regulator 32 whichdelivers oxygen to the helmet via the rotational bushing and disconnectbearing assembly, a pressure transfer connector 29 for connecting thevest to an associated torso pressure garment or coverall, and adjustablesupport springs 31 for providing helmet support and stability.Alternately, the vest assembly 12 may be replaced with an entire torsoor coverall pressure garment incorporating the aforementioned features.It will be seen from FIG. 1 that the bearing structure 24 is below theneck seal 26 at a location surrounding the base of the pilot's neck.

FIG. 2 shows a lightweight, headborne cap-type communications carrier 40which conforms to the user's head. The communications carrier isavailable in various sizes to fit the particular use and is worn inconjunction with the non-conformal helmet 10. Lightweight andlow-profile ear cups 42 provide noise attenuation and containcommunication receivers 43. In addition, a low-profile microphone 44 andboom assembly 45 are integrated at the frontal portion of the carrier.The receivers and microphone receive communication data via acommunications cord 46 which is coupled during use with thecommunications cable 30.

Since the carrier 40 conforms to the head of the wearer, the carrieralso serves as an ideal platform for mounting air crew physiologicalstatus monitoring devices (not shown) such as loss of consciousnessmonitoring systems which require intimate contact with the head.Additionally, 3-D auditory systems may be integrated with thenon-conformal helmet 10 and the communications carrier 40, for improvedpilot situational awareness. For extremely high noise environments, anoptional electronic noise canceling system tailored to and integral withthe helmet 10 augments the passive noise attenuation provided by thecombination of the helmet and the communications carrier.

Shock attenuating pads 48a are integrated with the communicationscarrier at the top forehead and top side locations to buffer headcontact with the inside surface of the helmet 10. An adjustable nape(not shown) and chin strap 49 is provided for size adjustment. Either anunder-the-chin strap or a chin cup arrangement may be utilized,depending upon individual preference. A comfort/absorption pad 48bintegrated across the brow, temple, and upper cheek areas, providescomfort and perspiration absorption under warm operating conditions.

When worn by the pilot, the non-conformal helmet 10 provides a pressureenclosure which has no direct contact with the head of the pilot, thusallowing the wearer's head to freely rotate within the helmet 10. Thecommunications carrier 40 is worn directly on the head of the pilotinside the helmet 10 for communications and buffet protection purposes.Nominal clearance between the communications carrier and the helmetvaries depending upon the head size of the user.

Turning now to FIGS. 3 and 4, an automatic helmet rotation system 50according to the present invention is shown. The automatic helmetrotation system includes automatic tracking circuitry 52, post-processdriver circuitry 54, and a power converting source 51, such as thoseused in automatic video tracking (AVT) systems produced by ISCAN® ofCambridge, Ma. The AVTs are real-time digital image processors whichautomatically track the movement of contrasting targets within the fieldof view of an electro-optic image sensor such as a video camera or aforward-looking infrared imager.

According to an exemplary embodiment of the present invention, aminiature real-time electronic imager 56 is mounted on the rear externalportion of the helmet 10. The imager 56 optically tracks the position ofa suitably contrasting target 64, such as an LED array orelectro-luminescent strip which is fixed on the communication carrier40. The imager 56 tracks the target through an optical viewing port 62provided at the rear portion of the helmet. The viewing port 62 may beconfigured to be approximately 5 cm in diameter. As the pilot's headmoves within the helmet 10 in relation to the fixed imager 56, an errorsignal is generated by the imager for processing by the automatictracking circuitry 52 in order to determine the direction of headmovement The automatic tracking circuitry 52 recognizes and tracks thetarget movement and generates data corresponding to the position of thetarget within the field of view of the imager 56. The tracking circuitrypreferably computes target position at a 60 Hz rate and is not affectedby smaller noise or clutter which may be present in the image containingthe target.

The post-process driver circuitry 54 operates to receive the datadetermining the direction of head motion and produces control signalsfor transmission to a motor 58, which in turn rotates a gear 59 in thedirection of the last-detected head motion. The gear 59 meshes with gearsegments 60 associated with the bushing assembly 20 for rotating thehelmet in the horizontal directions. The post-process driver circuitry54 continually adjusts the control signals in order to maintain properdirectional rotation of the helmet 10 until subsequent target movementis detected, thus maintaining the helmet in a predetermined positionwith respect to the wearer's head. A manual override feature may beintegrated with the system in order to override the rotation system 50as described.

All of the system electronics may be powered via a 28 VDC source whichis available to the helmet in conventional pilot pressure suit systems.The power source converter 51 operates to transform the 28 VDC to ±12VDC and 5 VDC necessary for the operation of the imager 56, theautomatic tracking circuitry 52, and the post-process driver circuitry54.

The above-described components are preferably integrated to fit onto therear portion of the non-conformal helmet 10 such as that (model S1032)manufactured by David Clark Company, Inc., of Worcester, Ma. Customsurface mounted circuitry may be fabricated to meet size and weightspecifications. Preferably, the configuration will be such that onlyapproximately two pounds of additional weight will be added to thehelmet 10. Furthermore, the imager 56 is preferably provided within anarea protruding approximately two inches outward from the helmet rearexterior. The tracking and post process circuitry may be integrated witha custom circuit board assembly designed to fulfill the above designrequirements.

The integrated pilot protective system in accordance with the presentinvention is also configured to restrain the pilot within the cockpitseat 70 in addition to the restraint provided by conventional beltstraps 72. With reference to FIGS. 5-7, a restraining anchor 74 issecured to the rear base portion of the disconnect bearing assembly 24at a location proximate to the base of the pilot's neck. The restraininganchor is releasably coupled to a strap 76 which is part of an inertiaoperated restraint system (not shown), e.g., shoulder harness inertiawheels, by a quick disconnect coupler 75. The restraining anchorprovides excellent helmet and upper body restraint via the retractablestrap 76 during high acceleration flight and for ejection. Such upperbody and head restraint during the ejection sequence is critical topreventing injury to the pilot. Furthermore, since the restraint anchor74 is affixed to the disconnect bearing assembly 24 below the rotatingbushing 20 of the helmet, there is total freedom of mobility of thehelmet and helmet rotation during normal operating conditions.

The foregoing description has been set forth to illustrate the inventionand is not intended to be limiting. Since modifications of the describedembodiments incorporating the spirit and substance of the invention mayoccur to persons skilled in the art, the scope of the invention shouldbe limited solely with reference to the appended claims and equivalentsthereof.

What is claimed is:
 1. An integrated pilot protection and restraintsystem operable in conjunction with a cockpit seat, said systemcomprising:a garment which envelops at least the upper torso of thepilot's body; an annular bearing structure configured to surround thebase of the pilot's neck, said bearing structure being integrated withsaid garment and operable for supporting a helmet; a helmet removablycoupled to and rotatively carried by said bearing structure; arestraining anchor disposed on a rear portion of said bearing structureproximate to the base of the pilot's neck; and a retractable restrainingdevice coupled to said restraining anchor, said restraining device beingoperable under emergency conditions to urge said bearing structure andsaid garment rearwardly and to thereby provide helmet and upper bodysupport against said cockpit seat.
 2. The system of claim 1, whereinsaid annular bearing structure comprises a helmet rotation portion andnon-rotating base portion.
 3. The system of claim 2, wherein saidrestraining anchor is disposed on said rear portion of said annularbearing structure at said non-rotating base portion proximate to thebase of the pilot's neck.
 4. The system of claim 1, wherein saidretractable restraining device comprises a harness and inertial reelassembly.
 5. The system of claim 4, wherein said harness is releasablycoupled to said restraining anchor.